2008 Mercury Grand Marquis Owner's Manuals

Increasing the inflation pressure beyond this pressure will not increase
the tire’s load carrying capability.
•kPa:Kilopascal, a metric unit of air pressure.
•PSI:Pounds per square inch, a standard unit of air pressure.
•Cold inflation pressure:The tire pressure when the vehicle has
been stationary and out of direct sunlight for an hour or more and
prior to the vehicle being driven for 1 mile (1.6 km).
•Recommended inflation pressure:The cold inflation pressure found
on the Safety Compliance Certification Label or Tire Label located on
the B-Pillar or the edge of the driver’s door.
•B-pillar:The structural member at the side of the vehicle behind the
front door.
•Bead area of the tire:Area of the tire next to the rim.
•Sidewall of the tire:Area between the bead area and the tread.
•Tread area of the tire:Area of the perimeter of the tire that
contacts the road when mounted on the vehicle.
•Rim:The metal support (wheel) for a tire or a tire and tube assembly
upon which the tire beads are seated.
INFLATING YOUR TIRES
Safe operation of your vehicle requires that your tires are properly
inflated. Remember that a tire can lose up to half of its air pressure
without appearing flat.
Every day before you drive, check your tires. If one looks lower than the
others, use a tire gauge to check pressure of all tires and adjust if
required.
At least once a month and before long trips, inspect each tire and check
the tire pressure with a tire gauge (including spare, if equipped). Inflate
all tires to the inflation pressure recommended by Ford Motor Company.
Use a tire gauge to check the tire inflation pressure, including the spare
(if equipped), at least monthly and before long trips. You are strongly
urged to buy a reliable tire pressure gauge, as automatic service station
gauges may be inaccurate. Ford recommends the use of a digital or
dial-type tire pressure gauge rather than a stick-type tire pressure gauge.
Use the recommended cold inflation pressure for optimum tire
performance and wear. Under-inflation or over-inflation may cause
uneven treadwear patterns.
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Under-inflation is the most common cause of tire failures and
may result in severe tire cracking, tread separation or
blowout
,
with unexpected loss of vehicle control and increased risk of injury.
Under-inflation increases sidewall flexing and rolling resistance,
resulting in heat buildup and internal damage to the tire. It also may
result in unnecessary tire stress, irregular wear, loss of vehicle control
and accidents. A tire can lose up to half of its air pressure and not
appear to be flat!
Always inflate your tires to the Ford recommended inflation pressure
even if it is less than the maximum inflation pressure information found
on the tire. The Ford recommended tire inflation pressure is found on
the Safety Compliance Certification Label or Tire Label which is located
on the B-Pillar or the edge of the driver’s door. Failure to follow the tire
pressure recommendations can cause uneven treadwear patterns and
adversely affect the way your vehicle handles.
Maximum Permissible Inflation Pressureis the tire manufacturer’s
maximum permissible pressure and/or the pressure at which the
maximum load can be carried by the tire. This pressure is normally
higher than the manufacturer’s recommended cold inflation pressure
which can be found on the Safety Compliance Certification Label or Tire
Label which is located on the B-Pillar or the edge of the driver’s door.
The cold inflation pressure should never be set lower than the
recommended pressure on the Safety Compliance Certification Label or
Tire Label.
When weather temperature changes occur, tire inflation pressures also
change. A 10°F (6°C) temperature drop can cause a corresponding drop
of 1 psi (7 kPa) in inflation pressure. Check your tire pressures
frequently and adjust them to the proper pressure which can be found
on the Safety Compliance Certification Label or Tire Label.
To check the pressure in your tire(s):
1. Make sure the tires are cool, meaning they are not hot from driving
even a mile.
If you are checking tire pressure when the tire is hot, (i.e. driven more
than 1 mile [1.6 km]), never “bleed” or reduce air pressure. The tires are
hot from driving and it is normal for pressures to increase above
recommended cold pressures. A hot tire at or below recommended cold
inflation pressure could be significantly under-inflated.
Note:If you have to drive a distance to get air for your tire(s), check
and record the tire pressure first and add the appropriate air pressure
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when you get to the pump. It is normal for tires to heat up and the air
pressure inside to go up as you drive.
2. Remove the cap from the valve on one tire, then firmly press the tire
gauge onto the valve and measure the pressure.
3. Add enough air to reach the recommended air pressure.
Note:If you overfill the tire, release air by pushing on the metal stem in
the center of the valve. Then recheck the pressure with your tire gauge.
4. Replace the valve cap.
5. Repeat this procedure for each tire, including the spare.
Note:Some spare tires operate at a higher inflation pressure than the
other tires. For T-type/mini-spare tires (seeDissimilar Spare
Tire/Wheel Informationsection for description): Store and maintain at
60psi (4.15 bar). For Full Size and Dissimilar spare tires (seeDissimilar
Spare Tire/Wheel Informationsection for description): Store and
maintain at the higher of the front and rear inflation pressure as shown
on the Tire Label.
6. Visually inspect the tires to make sure there are no nails or other
objects embedded that could poke a hole in the tire and cause an air
leak.
7. Check the sidewalls to make sure there are no gouges, cuts or bulges.
TIRE CARE
Inspecting your tires
Periodically inspect the tire treads for uneven or excessive wear and
remove objects such as stones, nails or glass that may be wedged in the
tread grooves. Check for holes or cuts that may permit air leakage from
the tire and make necessary repairs. Also inspect the tire sidewalls for
cracking, cuts, bruises and other signs of damage or excessive wear. If
internal damage to the tire is suspected, have the tire demounted and
inspected in case it needs to be repaired or replaced. For your safety,
tires that are damaged or show signs of excessive wear should not be
used because they are more likely to blow out or fail.
Improper or inadequate vehicle maintenance can cause tires to wear
abnormally. Inspect all your tires, including the spare, frequently, and
replace them if one or more of the following conditions exist:
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Tire wear
When the tread is worn down to
1/16th of an inch (2 mm), tires must
be replaced to help prevent your
vehicle from skidding and
hydroplaning. Built-in treadwear
indicators, or “wear bars”, which
look like narrow strips of smooth
rubber across the tread will appear
on the tire when the tread is worn
down to 1/16th of an inch (2 mm).
When the tire tread wears down to
the same height as these “wear bars”, the tire is worn out and must be
replaced.
Damage
Periodically inspect the tire treads and sidewalls for damage (such as
bulges in the tread or sidewalls, cracks in the tread groove and
separation in the tread or sidewall). If damage is observed or suspected
have the tire inspected by a tire professional. Tires can be damaged
during off-road use, so inspection after off-road use is also
recommended.
Age
Tires degrade over time depending on many factors such as
weather, storage conditions, and conditions of use (load, speed,
inflation pressure, etc.) the tires experience throughout their lives.
In general, tires should be replaced after six years regardless of tread
wear. However, heat caused by hot climates or frequent high loading
conditions can accelerate the aging process and may require tires to be
replaced more frequently.
You should replace your spare tire when you replace the road tires or
after six years due to aging even if it has not been used.
U.S. DOT Tire Identification Number (TIN)
Both U.S. and Canada Federal regulations require tire manufacturers to
place standardized information on the sidewall of all tires. This
information identifies and describes the fundamental characteristics of
the tire and also provides a U.S. DOT Tire Identification Number for
safety standard certification and in case of a recall.
This begins with the letters “DOT” and indicates that the tire meets all
federal standards. The next two numbers or letters are the plant code
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designating where it was manufactured, the next two are the tire size
code and the last four numbers represent the week and year the tire was
built. For example, the numbers 317 mean the 31st week of 1997. After
2000 the numbers go to four digits. For example, 2501 means the 25th
week of 2001. The numbers in between are identification codes used for
traceability. This information is used to contact customers if a tire defect
requires a recall.
Tire replacement requirements
Your vehicle is equipped with tires designed to provide a safe ride and
handling capability.
Only use replacement tires and wheels that are the same size,
load index, speed rating and type (such as P-metric versus
LT-metric or all-season versus all-terrain) as those originally provided
by Ford. The recommended tire and wheel size may be found on either
the Safety Compliance Certification Label or the Tire Label which is
located on the B-Pillar or edge of the driver’s door. If this information
is not found on these labels then you should consult your Ford dealer.
Use of any tire or wheel not recommended by Ford can affect the
safety and performance of your vehicle, which could result in an
increased risk of loss of vehicle control, vehicle rollover, personal injury
and death. Additionally the use of non-recommended tires and wheels
could cause steering, suspension, axle or transfer case/power transfer
unit failure. If you have questions regarding tire replacement, see an
authorized dealer.
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When mounting replacement tires and wheels, you should not
exceed the maximum pressure indicated on the sidewall of the
tire to set the beads without additional precautions listed below. If the
beads do not seat at the maximum pressure indicated, re-lubricate and
try again.
When inflating the tire for mounting pressures up to 20 psi greater
than the maximum pressure on the tire sidewall, the following
precautions must be taken to protect the person mounting the tire:
1. Make sure that you have the correct tire and wheel size.
2. Lubricate the tire bead and wheel bead seat area again.
3. Stand at a minimum of 12 feet away from the tire wheel assembly.
4. Use both eye and ear protection.
For a mounting pressure more than 20 psi greater than the maximum
pressure, a Ford Dealer or other tire service professional should do the
mounting.
Always inflate steel carcass tires with a remote air fill with the person
inflating standing at a minimum of 12 ft. away from the tire wheel
assembly.
Important:Remember to replace the wheel valve stems when the road
tires are replaced on your vehicle.
It is recommended that the two front tires or two rear tires generally be
replaced as a pair.
The tire pressure sensors mounted in the wheels (originally installed on
your vehicle) are not designed to be used in aftermarket wheels.
The use of wheels or tires not recommended by Ford Motor Company
may affect the operation of your Tire Pressure Monitoring System.
If the TPMS indicator is flashing, your TPMS is malfunctioning. Your
replacement tire might be incompatible with your TPMS, or some
component of the TPMS may be damaged.
Safety practices
Driving habits have a great deal to do with your tire mileage and safety.
•Observe posted speed limits
•Avoid fast starts, stops and turns
•Avoid potholes and objects on the road
•Do not run over curbs or hit the tire against a curb when parking
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If your vehicle is stuck in snow, mud, sand, etc.,do notrapidly
spin the tires; spinning the tires can tear the tire and cause an
explosion. A tire can explode in as little as three to five seconds.
Do not spin the wheels at over 35 mph (56 km/h). The tires may
fail and injure a passenger or bystander.
Highway hazards
No matter how carefully you drive there’s always the possibility that you
may eventually have a flat tire on the highway. Drive slowly to the
closest safe area out of traffic. This may further damage the flat tire, but
your safety is more important.
If you feel a sudden vibration or ride disturbance while driving, or you
suspect your tire or vehicle has been damaged, immediately reduce your
speed. Drive with caution until you can safely pull off the road. Stop and
inspect the tires for damage. If a tire is under-inflated or damaged,
deflate it, remove wheel and replace it with your spare tire and wheel. If
you cannot detect a cause, have the vehicle towed to the nearest repair
facility or tire dealer to have the vehicle inspected.
Tire and wheel alignment
A bad jolt from hitting a curb or pothole can cause the front end of your
vehicle to become misaligned or cause damage to your tires. If your
vehicle seems to pull to one side when you’re driving, the wheels may be
out of alignment. Have an authorized dealer check the wheel alignment
periodically.
Wheel misalignment in the front or the rear can cause uneven and rapid
treadwear of your tires and should be corrected by an authorized dealer.
Front wheel drive (FWD) vehicles and those with an independent rear
suspension (if equipped) may require alignment of all four wheels.
The tires should also be balanced periodically. An unbalanced tire and
wheel assembly may result in irregular tire wear.
Tire rotation
Rotating your tires at the recommended interval (as indicated in the
scheduled maintenance informationthat comes with your vehicle) will
help your tires wear more evenly, providing better tire performance and
longer tire life.
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•Rear Wheel Drive (RWD)
vehicles/Four Wheel Drive
(4WD)/ All Wheel Drive (AWD)
vehicles (front tires at top of
diagram)
Sometimes irregular tire wear can be corrected by rotating the tires.
Note:If your tires show uneven wear ask an authorized dealer to check
for and correct any wheel misalignment, tire imbalance or mechanical
problem involved before tire rotation.
Note:Your vehicle may be equipped with a dissimilar spare tire/wheel. A
dissimilar spare tire/wheel is defined as a spare tire and/or wheel that is
different in brand, size or appearance from the road tires and wheels. If
you have a dissimilar spare tire/wheel it is intended for temporary use
only and should not be used in a tire rotation.
Note:After having your tires rotated, inflation pressure must be checked
and adjusted to the vehicle requirements.
INFORMATION CONTAINED ON THE TIRE SIDEWALL
Both U.S. and Canada Federal regulations require tire manufacturers to
place standardized information on the sidewall of all tires. This
information identifies and describes the fundamental characteristics of
the tire and also provides a U.S. DOT Tire Identification Number for
safety standard certification and in case of a recall.
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Owners Guide (post-2002-fmt)
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